The structure and dynamics of DNA in the gas phase

The impact of the transfer from water to the vacuum in the duplex DNA has been explored by using long molecular dynamic simulations. In opposition to chemical intuition, it is found that vaporization of DNA, even at high temperatures, does not lead to a total disruption of the double helix. Rather, the DNA duplex preserves gross structural, energetic, and dynamic features of the conformation of the double helix in aqueous solution. Thus, the two strands remain bound, the global structure has a slight helicity, and the total number of DNA-DNA interactions is not dramatically different from that found in solution. The results provide detailed structural and dynamic information useful to complement current mass spectroscopy studies of DNA structures.